These specifications cover molded cups 51 mm (2 in) in diameter and under, compounded from high temperature resistant rubber for use in hydraulic actuating cylinders employing motor vehicle brake fluid conforming to the requirements specified in SAE J1703 and SAE J1705. These specifications cover the performance tests of hydraulic brake cups under specified conditions and do not include requirements relating to chemical composition, tensile strength, and elongation of the rubber compound. Disc brake seals are not covered by this document.